Deferred queuing in a buffered switch

A data switch comprising:

• a) an input port for receiving a data packet;
• b) a buffer for temporarily storing and retrieving at least the beginning of the data packet;
• c) destination determination logic for determining a switch destination for the data packet;
• d) congestion status determination logic for determining a congestion status of the switch destination;
• e) a deferred queue for storing header information relating to the data packet;
• f) a queue controller for directing the data packet to the deferred queue if the congestion status is congested and for directing the data packet to the switch destination if the congestion status is non-congested;
• g) deferred queue state logic for analyzing the packet on the deferred queue and for forwarding the packet to the switch destination if the congestion status has changed to non-congested;
• and
• h) a backup queue for storing additional data packets when the deferred queue state logic is analyzing a packet.

A data switch that switches data packets through the switch from ingress ports to destination ports comprising:

• a) a buffer memory at each ingress port for storing a portion of the data packets at known locations;
• b) a routing module that determines switch destination addresses and other packet header information for the data packets;
• c) a deferred queue and a backup queue for storing packet header information, including their locations in the buffer;
• and
• d) a next header logic that selects a next data packet to be sent through the switch, the next data packet being chosen from incoming data packets analyzed by the routing module, the deferred queue, and the backup queue,
• wherein the deferred queue is utilized for storing packet header information if the switch destination is congested, and
• wherein the backup queue is utilized for storing packet header information if header information in the deferred queue is being analyzed.